No of Pages: If there is an application with hundreds or thousands of web pages then the time and the effort in the development of automation framework will be high.
Maintenance Overhead: The cost increases when maintenance overhead increases which are due to the maintenance of large class as they break the OO design principle.
Programming Best Practices: The development of POM framework for multiple pages is equal to developers work thus testers should be highly knowledgeable in programming best practices.
Not Generic Model: Page object model is not a generic model and its specific to the applications.
The best approach to overcome the above challenges is by refactoring the POM concept to Screenplay Pattern.
If that menu has been created by using select tag then we can use the methods selectByValue() or selectByIndex() or selectByVisibleText(). These are the methods of the Select class.
If the menu has not been created by using the select tag then we can simply find the xpath of that element and click on that to select.
Actions act = new Actions(driver);
WebElement source = driver.findElement(By.xpath("")); //source element which you want to drag
WebElement target = driver.findElement(By.xpath("")); //target where you want to drop
act.dragAndDrop(source, target).perform();
To handle alert pop-ups, we need to 1st switch control to alert then click on ok or cancel then move control back to main page.
String mainPage = driver.getWindowHandle();
Alert alt = driver.switchTo().alert(); // to move control to alert popup
alt.accept(); // to click on ok.
alt.dismiss(); // to click on cancel.
//Then move the control back to main web page
driver.switchTo().window(mainPage);